If you put your whole body inside water than there's no worrying of the water not touching your body.
There's a funny story when someone went to a sheikh and told the sheikh that he put his whole body in water, but he wasn't sure if the water touched the body. Sheikh told him that he's free from ever praying 😂 because yk, people without actual mind aren't eligible to pray. Ofc your body was in touch with water.
Maljis will explain better, but Insha'Allah you're in the state of purity